Dr. Paul Vasey has spent much of his life studying sexual behavior across species and across cultures. For two decades, he observed Japanese macaques—a species of monkey—in mountains outside of Kyoto. During his time in Japan, Dr. Vasey consistently observed female macaques sexual mounting other females. If fact, he estimates that only 20% of these female monkeys are exclusively heterosexual. This results in an intersexual mate competition, whereby males must compete with both female and male members of their species to find a female mate. Fascinated, Dr.

Researchers at Utrecht University and the New York State Psychiatric Institute collaborated on a meta-analysis of research on adolescent sexual behavior. The goal was to analyze how this behavior is related to adolescents' perceptions of three types of sexual peer norms, including how sexually active their peers are, how much their peers would approve of being sexually active, or how much they feel pressured by their peers to have sex.

People's emotional reactions and desires in initial romantic encounters determine the fate of a potential relationship. Responsiveness may be one of those initial "sparks" necessary to fuel sexual desire and land a second date. However, it may not be a desirable trait for both men and women on a first date. Does responsiveness increase sexual desire in the other person? Do men perceive responsive women as more attractive, and does the same hold true for women's perceptions of men? A study published in Personality and Social Psychology Bulletin seeks to answer those questions.

Previous research has shown that men perceive the color red on a woman to be a signal of sexual receptivity. Women are more likely to wear a red shirt when they are expecting to meet an attractive man, relative to an unattractive man or a woman. But do women view other women in red as being more sexually receptive? And would that result in a woman guarding her mate against a woman in red? A study published in Personality and Social Psychology Bulletin sought to answer these questions.